Can an ob/gyn mistake trich infection for a yeast infection? my doctor just looked at my vagina and said i have a yeast infection, but he didn't test

Could be both...: Yeast infections have a characteristic appearance so there is a good chance you have a yeast infection. But other infections, including trichomonas, do not have obvious appearances & are best diagnosed by looking at a swab under the microscope. It's possible you could have both yeast & another infection like trich. You could wait to see if symptoms resolve with treatment but also talk to your doc.